The Geology of Ensign Peak

Ensign peak is located at the very north point of Salt Lake City right behind the Capitol
building. The hike to ensign peak is fairly popular because of the view at the top and the easiness
of it. According to the Utah Geological Survey interactive map, the area where ensign peak lays
is covered with conglomerate, and humbug formation. The area has a simple geologic history
and even falls on the famous Wasatch fault line. The trailhead has many examples of weathering
and erosion from the very bottom to the very top of the peak. This research paper will discuss
observations made and the geology of the peak.
Along with the geologic features of ensign peak, it also has a religious history to it. The
peak got its name when Brigham Young, the President of the Church of Jesus Christ of LatterDay Saints at the time, led his Mormon pioneers to the Salt Lake Valley. Young and a few others
hiked the peak and that is when he said that it “was a proper place to raise an ensign to the
nations”. Young had also claimed that he had a vision of the Joseph Smith showing him a peak
and he told Young to “build under the point where the colors fall, and you will prosper and have
peace” (Smith, 1927). The peak also has a monument that is made of the stones that they
collected along the Mormon Trail (Arave 1991).
The Wasatch fault is the most significant geologic feature at ensign peak since it lies at
the base of it. The fault extends from Fayette, Utah which is just south of Provo, all the way up
to Malad City which is not to far up from the Northern border of Utah. A fault is defined as a
break in the crust where rocks slip past each other (Reynolds, Johnson, Kelly, Morin, & Carter,
2008). According to the Utah Geologic Survey, the Wasatch fault is considered to be a normal
fault “because the slip is mostly vertical – the mountain block (Wasatch Range) moves upward
relative to the adjacent downward-moving valley block.”
The area where the peak lies is very mountainous, which can be seen in photo 5, which
has to be a direct result of the Wasatch range and fault. What formed the two are earthquakes that
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first pushed up on the Wasatch range and that left the Wasatch fault line that falls at the base of
ensign peak (Utah Geologic Survey). Along with being mountainous, it is also either very grassy
in some areas or really rocky in others. The rocky parts are more predominant and exhibit many
years of weathering and erosion that will be discussed in the next paragraph. The grassy areas
also include the variety of oak brush which indicates well soiled areas.
Erosion and weathering is inevitable, it’s been around since the beginning of time and it
will be around until the end of time. It’s what causes rocks to move around and get their angular
or round shapes. In the photos at the end of this essay, they all show erosion in different ways. In
photo three, it shows a small path where smaller rocks have fallen down the side of the cliff. This
is a result of wind or water erosion. More specifically photo five also shows how the rocks the
west side of the top of the peak eroded away throughout time and created the smooth/angular
rocky side.
Around the world there are many different rocks types that are very prominent in many
different areas. The majority of the solid part of Earth contains igneous or metamorphic rock but
most of the solid surface contains sedimentary rocks. Utah alone has many different rocks from
our Wasatch Mountains, all they way to down south with the famous arches. The majority of the
Salt Lake Valley consists of quaternary Lake Bonneville deposits and quaternary flood plain
deposits with rocks from the Precambrian era all the way to the Cretaceous era (State of Utah,
Department of Natural Resources, Utah Geological and Mineral Survey).
Ensign peak lies just above and to the right of the Salt Lake Valley. According to the
Department of Natural Resources and the Utah Geologic and Mineral Survey, the peak consists
of tertiary sedimentary rocks that are both young and old but with the older rocks being more
prominent. The rocks that were on the trail did prove this information to be true. Also, according
to the Utah Geological Survey interactive map, ensign peak is conglomerate dominant.
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Conglomerate rocks are a type of detrital sedimentary rock, which are rock types that can consist
of rock fragments or be made from clay or quartz.
The conglomerate area consists of a pale brown and grayish tone of colors. The sediments
and rocks are poorly sorted and of course consists of conglomerate and sandstone type rocks. It
also contains coarse, partially rounded and partially angular chucks of quartzite and limestone
with chucks of metamorphic rocks toward the northern end of the peak. The peak does include
small areas around it that have humbug formation. The humbug formation is from the upper
Mississippian era and consists of gray limestone and dolomite. It also contains beds of reddishbrown sandstone and some interbeds of red siltstone but the siltstone is rare (Utah Geologic
Survey Interactive Map).
Along the trail there was more dirt and gravel than rocks. There were more rocks toward
the top of the peak. The first part of the trial consists of what is seen in photo six which is grass
and dirt. The gravel deposits are what was deposited and left of the ancient Lake Bonneville (The
Department of Natural Resources and the Utah Geologic and Mineral Survey). More than half
way up the trail is where all the rocks are. The rocks seen, for the most part, are all sedimentary
rocks. Three of the rock samples collected were all very different. The first was a conglomerate,
which was the dominant rock type that was seen at the top of the peak. The second looked like a
sandstone rock with the tint of red to it. The last rock was part of the organic sedimentary rock
group, a coal.
Ensign peak is an area that has years of geologic history to it, along with religious history.
To the average person, all the area is, is rocks, plants, dirt, and grass. But research shows that it’s
actually a history filled area that is interesting to learn about. The peak shows a great example of
erosion, weathering, sedimentary rock types, gravel and dirt deposits, and old time rock geology.
Along with the geological history, the hike is also a local favorite and is very family and dog
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friendly. The site will continue to be a favorite because of the beautiful view and the religious
symbolism of it.